Vehicles operating in an autonomous mode (e.g., driverless) can relieve occupants, especially the driver, from some driving-related responsibilities. When operating in an autonomous mode, the vehicle can navigate to various locations using onboard sensors, allowing the vehicle to travel with minimal human interaction or in some cases without any passengers.
Similar to human beings making various decisions while driving, an autonomous vehicle always has to make instant driving decisions according to the actual surrounding environment, which may include certain driving conditions, surrounding obstacles, and traffic conditions. Such environment often influences movement of vehicles, and it may be difficult to determine or identify the next maneuver a vehicle will make in the environment. Human beings, however, can easily identify and resolve the difficulties, for example, by using the naked eyes. Unfortunately, such may be challenging for autonomous vehicles.